A fun build-it-yourself project is to create this “Crazyflie” a homemade miniature Quadcopter that uses a Printed Circuit Board (PCB). The video at the link shows the tiny flying machine zipping around effortlessly.

Despite its tinyness, the quadcopter includes a charging port, radio, 3-axis accelerometer, two gyroscopes, and a lightweight 110 mAh LiPO battery that gives it about four and a half minutes of flying time